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31.
DH lines derived from cabbage cvs. Kamienna G?owa, S?awa z Enkhuizen and Langendijker, representing R1 generation, were analysed by the use of RAPD markers for their diversity and uniformity. For the evaluation of genetic diversity, eight primers yielding informative bands were used. Of the total of 83 RAPD bands scored in this study, 16.9% were polymorphic between a set of 13 DH lines. The similarity of the DH lines, estimated by Jaccard's coefficient, was depicted in the UPGMA dendrogram. Fourteen generated informative RAPD bands allowed the identification of DH lines developed from each cultivar. The evaluation of the uniformity for six closely related DH lines was possible by the use of three primers which generate one or two polymorphic bands. The lack of differences among ten plants of the five investigated DH lines manifested their uniformity. One line showed intraline polymorphism with two RAPD primers. The occurrence of the differences at the molecular level among ten plants indicated that their parental R0 plant was probably obtained from somatic cells, not by androgenesis.  相似文献   
32.
Seven enzymatic systems in F1 Aegilops kotschyi and Ae. biuncialis x Secale cereale hybrids, Aegilops kotschyi x S. cereale amphiploids and their parental species (Ae. kotschyi, Ae. biuncialis and S. cereale) were analysed by starch and polyacrylamide gel electrophoresis. Five of them (phosphoglucose isomerase, glutamic oxalacetic transaminase, esterase, acid phosphatase, and diaphorase) were polymorphic and two (malic dehydrogenase and superoxide dismutase) were monomorphic. Several isophorms of phosphoclucose isomerase, esterase, acid phosphatase, and diaphorase were detected in some hybrids and amphiploids, but absent in the parents. The role of regulators, translocations and recombination is discussed in relation to the origin of these new isophorms. Some parental isozymes were absent both in hybrids and amphiploids, probably as a result of the suppression of structural genes in new combinations of the three genomes.  相似文献   
33.
Tettigonia ussuriana and T. dolichopoda maritima differ in the length of tegmina, details in venation, and in females in details of the subgenital plate. The two species of the genus Tettigonia have the same number and morphology of autosomes but a different morphology of the X chromosome: in T. ussuriana it is metacentric, whereas in T. dolichopoda maritima acrocentric. In both species, euchromatic zones and breaks of one or to chromatids during meiosis and mitosis in the X chromosome were observed. Additionally, B chromosomes were noted in most individuals of both species.  相似文献   
34.
Anorexia is possibly one of the most important causes of malnutrition in uremic patients. The cause of this abnormality is still unknown. Considering that: (a) NPY is one of the most important stimulants of food intake; (b) eating is a central nervous system regulated process and (c) NPY is expressed in hypothalamus, we hypothesized that the decrease of NPY gene expression in the hypothalamus could be an important factor contributing to anorexia associated with uremic state. In contrast to the prediction, the results presented in this paper indicate that the NPY gene expression in the hypothalamus of chronic renal failure (CRF) rats was significantly higher than in the hypothalamus of control (pair-fed) rats. Moreover, we found that serum NPY concentration in CRF rats was higher than in control (pair-fed) animals. The increase of plasma NPY concentration in CRF rats may be due to the greater synthesis of the neuropeptide in liver, since higher level of NPY mRNA was found in liver of CRF rats. The results obtained revealed that experimental chronic renal failure is associated with the increase of NPY gene expression in hypothalamus and liver of rats.  相似文献   
35.
In plants, an electrical potential and circumnutation disturbances are a part of a response to environmental and internal stimuli. Precise relations between electrical potential changes and circumnutation mechanisms are unclear. We have found recently that glutamate (Glu) injection into Helianthus annuus stem induced a series of action potentials (APs) and a transient decrease in circumnutation activity. A theoretical explanation for this finding is discussed here taking into considerations data about the ion mechanism of AP and circumnutation as well as about the metabolic and signaling pathways of glutamate and their possible interactions.Key words: action potential, circumnutation, elongation, glutamate, Helianthus annuus, plant movement  相似文献   
36.
Edema, proteinuria, hypertension (EPH-gestosis), most commonly termed as pre-eclampsia, is the most common pregnancy-associated pathological syndrome. It is accompanied by a thorough remodelling of extracellular matrix in the umbilical cord tissues. It is commonly known that the presence of serum in culture medium strongly stimulates many functions of cells cultured in vitro. It was decided to check how the pre-eclamptic serum affects the fibroblast division in culture. Ki-67 is a protein present in proliferating cells and can be detected during all phases of the cell cycle (G1, S, G2/M) but not in resting (G0) cells. PCNA (proliferating cell nuclear antigen) is an intranuclear polypeptide whose synthesis rate is at its maximum during the S-phase of the cell cycle. The expression of Ki-67 and PCNA was measured by immunocytochemical methods and biosynthesis of DNA was evaluated by [14C]-thymidine incorporation. The activity of pre-eclamptic umbilical cord serum (UC-serum) was found to be distinctly lower in comparison to control one. The expression of Ki and PCNA in fibroblast cultures treated with pre-eclamptic serum was also distinctly lower. Also the incorporation of [14C]-thymidine to DNA was lower than in the cultures treated with control UC-serum. It may by concluded that pre-eclampsia reduces the mitogenic activity of the umbilical cord serum.  相似文献   
37.
IL-2, the first cytokine discovered with T cell growth factor activity, is now known to have pleiotropic effects on T cells. For example, it can promote growth, survival, and differentiation of Ag-selected cells, or facilitate Ag-induced cell death of T cells when Ag persists, and in vivo, it is thought to contribute to the regulation of the size of adaptive T cell response. IL-2 is deficient in HIV-1 infection and has been used in the management of HIV-1-infected individuals undergoing antiretroviral therapy. In this study, we investigated how continuous low-dose IL-2 affected the CD4+ and CD8+ T cell response induced by two inoculations of a canarypox recombinant SIV-based vaccine candidate in healthy macaques chronically infected with SIVmac251. These macaques had normal levels of CD4+ T cells at the beginning of antiretroviral therapy treatment. Vaccination in the presence of IL-2 significantly augmented Gag-specific CD8+ T cell responses, but actually reduced Gag-specific CD4+ T cell responses. Although IL-2 at low doses did not change the overall concentration of circulating CD4+ or CD8+ T cells, it expanded the frequency of CD4+CD25+ T cells. Depletion of the CD4+CD25+ T cells in vitro, however, did not result in a reconstitution of Gag-specific CD4+ responses or augmentation of SIV-specific CD8+ T cell responses. Thus, we conclude that the decrease in virus-specific CD4+ T cell response may be due to IL-2-promoted redistribution of cells from the circulation, or due to Ag-induced cell death, rather than suppression by a T regulatory population.  相似文献   
38.
A new kinetic model is presented for analysis of experimental data of oxidation process catalyzed by milk xanthine oxidase. The kinetics for two substrates, xanthine and its analog 2-chloroadenine, in a broad pH range (5.8-9.0) are best described by an equation which is a rational function of degree 2:3 and 2:2, respectively.  相似文献   
39.
The C-banding patterns in the embryo chromosomes of the grasshopper Podisma pedestris (L.) from the Altai Mts are reported. The additional second C-heterochromatic arms in at least five pairs of autosomes and in the X-chromosome were revealed. The paracentromeric, interstitial, and telomeric C-bands were observed. The studied population of P. pedestris shows some differences in the distribution and amount of the heterochromatin in comparison with European populations.  相似文献   
40.

Punicic acid (PuA) is a conjugated linolenic acid (C18:3Δ9c,11t,13c) with a wide range of nutraceutic effects with the potential to reduce the incidence of a number of health disorders including diabetes, obesity, and cancer. It is the main component of seed oil from Punica granatum and Trichosanthes kirilowii. Previously, production of relatively high levels of this unusual fatty acid in the seed oil of transgenic Arabidopsis thaliana plant was accomplished by the use of A. thaliana fad3/fae1 mutant high in linoleic acid (18:2∆9c,12c) and by co-expression of P. granatum FATTY ACID CONJUGASE (PgFADX) with Δ12-DESATURASE (FAD2). In the current study, P. granatum cDNAs governing PuA production were introduced into the yeast Schizosaccharomyces pombe. Expression of PgFADX alone resulted in production of PuA at the level of 19.6% of total fatty acids. Co-expression PgFADX with PgFAD2, however, further enhanced PuA content to 25.1% of total fatty acids, the highest level reported to date for heterologous expression. Therefore, microbial systems can be considered as a potential alternative to plant sources for a source of PuA for nutraceutic applications.

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